1. Field of the Invention
The present invention relates to a multi-functional ultrasonic motor and an apparatus using this motor.
2. Description of Related Art
Traditionally, a plurality of motors have so been used to drive control objects many. In the case of drive-controlling at least two objects individually by one motor, a power transmission mechanism and a power switching mechanism is not so complex. However, in the case of drive-controlling three or more objects, the power transmission mechanism and the power switching mechanism to be used for this work become extremely complex and the overall size of the apparatus becomes large. Because there is a limit to the reduction in the size of the conventional motor and its peripheral structure, there is also a limit to the reduction in the overall size of the apparatus for mounting the motor.
A focus is now being placed on an ultrasonic motor as a motor which can have a small size. An ultrasonic motor that utilizes an oscillation of 20 kHz or above, can obtain a high torque even during a low-speed rotation and requires no gears for deceleration. The result is a quiete rotation and a simple structure. Further, since the ultrasonic motor does not require a member as a rotation axis, the motor is able to have a stator and a rotor formed in a cylinder shape respectively.